Gasless combustion is a specific type of combustion, where all initial reactants, as well as intermediate and final products, remain in condensed (solid or liquid) state. This process is of great interest because of its prospective applications in combustion synthesis of advanced materials. The stability of combustion wave propagation is an important factor in determining the quality of materials produced by combustion synthesis. In this work, a digital high-speed microscopic video recording method is used for direct observation and quantitative characterization of pulsating combustion in several gasless systems. The experimental data quantitatively describe, for the first time, oscillations of local instantaneous velocity at length scale about 10 mu m and time scale similar to 10(-3) s. Three systems investigated were: Ta-C, Nb-B, and Ti-C. Two new mechanisms of pulsating combustion were identified: crack-induced oscillations occur in Nb + B and Ta + C syst ems, while ignition-extinction oscillations take place during reaction in Ti + xC system.